<!doctype html>
<html lang="en" id="html">
        <head>
                <meta charset="utf-8">
                <meta name="viewport" content="width=device-width, initial-scale=1">
                <title>Test Page</title>
                <script>
window.addEventListener("load", () => {
  const observer = new MutationObserver((mutations, observer) => {
    let removed = false;
    for (const mutation of mutations) {
      for (let node of mutation.addedNodes) {
        node.remove();
        removed = true;
      }
    }
    if (removed) {
      observer.disconnect();
    }
  });
  observer.observe(document.body, { childList: true, subtree: true });
});
                </script>
        </head>
        <body id="body">
                <textarea id="content-input" rows="20" cols="80"></textarea>
        </body>
</html>
